What about the types int2, int3, float2, float3 etc

Question

I\'ve seen different code snippets using these types, but I haven\'t seen if they are defined in some or just defined in a \"local header file\"

Answer 1

These types aren't a part of standard C++. They might either be defined in some third-party library, or you're looking at some other dialect or language.

GPU code (Shader languages such as GLSL, Cg or HLSL, or GPGPU stuff like CUDA or OpenCL) typically defines types like these though, as names for the corresponding SIMD datatypes.